Question

Afla necunoscuta :
13-4x3:[2x11-1x5-(10x2-5xa)]+2x3=13

Answer 1

13-4·3:[2·11-1·5-(10·2-5·a)]+2·3=13
13-12:(22-5-20-5a)+6=13
13-12:(17-20-5a)=7
-12:(-3-5a)=-6/12
-3-5a=1/6
-5a=1/6+(3/1amplific cu 6)
-5a=1/6+18/6
-5a=19/6
-a= 95/6\(-1)
a=-95/6